For a brief moment this summer, sanity entered one of sports’ least rationale bazaars, the NBA free agency market. Sanity came in the form of shorter contracts. However, the moment was squandered and now, as teams round out the end of their rosters, it looks as if that window has closed.

First LeBron James wanted — and signed — a three-year extension with a player option for a fourth, two years less than what he was entitled to demand. Then, fellow class of 2003 draftees Dwyane Wade and Chris Bosh quickly followed suit and inked comparable deals.

After the signing, most of the attention focused on the fact that all three, each of whom was due to a be a restricted free agent at conclusion of the 2006–07 season, would be eligible for unrestricted free agency in the summer of 2010. This of course set the rumor mill swirling with possibilities, since even the Knicks will have cap room then. The party line was that the teams signing these deals — Cleveland, Miami, and Toronto — were putting enormous pressure on themselves to be desirable teams then.

No one focused on the fact that these teams — and every other NBA team — stands a far better chance of being consistently good if they make shorter pacts the norm. Imagine the impact on the free agent market if Cleveland’s team president, Danny Ferry, had said something to the effect of “we’re taking a chance on LeBron just as he’s taking a chance with us, and I hope every player and team is willing to make a similar gamble.”

It probably wouldn’t have been a total panacea to a hugely irrational market, but such a comment might have exerted some downward pressure on contract length, which is the biggest problem in salary cap management.

When most folks look at the salary cap, it’s easy to spot a space-hog contract like Kobe Bryant’s $105 million over the next five years and blame it for the Lakers being in the luxury tax zone. However, Bryant earns his keep. There are very, very few players who are capable of playing 83% of their team’s minutes and scoring 2,832 of the team’s 8,154 points (34.7%). What hurts the Lakers’ cap is the $17 million over the next two seasons given to Kwame Brown. Brown played in just over half of his team’s minutes, but during his burn, he produced 536 points or 6.5% of his team’s total and 473 or 13.7% of his team’s rebounds. In other words marginal players making major money are the cap killers and teams could have taken a step toward minimizing this damage by not pretending that the next Kwames are Kobes.

But they didn’t. Rather than using the James/Wade/Bosh deals as a benchmark, most teams went ahead and gave five-year deals to players who lack the track record to warrant them. I happen to like Marcus Banks’s chances of making Phoenix look like a smart team, but there was no reason to bank (sic) on a five-year deal. He wasn’t wanted by his old team, Minnesota, and there wasn’t a clamor for his services since his recent improvement occurred off the radar of most NBA executives. Banks was a good candidate for a “James”style contract of three years plus an option.

Swingman John Salmons’s five-year $25.5 million deal with Sacramento and Darius Songalia’s five-year $23 million pact with Washington are in the same vein.No one, outside of their agents and their families, regards these guys as impact players. Salmons is 26 and just had finished his fourth and best NBA season averaging 7.5 points per game on 42% shooting. Songalia, 28, who completed his third campaign this spring is a better bet having averaged 9.2 points on 48% shooting, but still he wasn’t particularly coveted either. There was no motivation to offer generous contracts like these other than throwing money around to prove to your fanbase that you’re trying win. In reality, overspending like this puts your closer to if not over the luxury tax threshold (teams with payrolls above the luxury tax line pay a dollar for dollar penalty). Teams over the threshold generally lack the flexibility to pursue good players even on the cheap.

Players do well to avoid long contracts too; just look at the biggest non-deal of the summer, Philadelphia’s failure to trade Allen Iverson. The biggest obstacle in moving the perennial all-star wasn’t his longstanding reputation as a handful, but rather his contract.The 31-year old guard is due to make $18.3 million next season, $20.1 million in 2007–08, and $21.9 in 2008–09 as part of a longterm extension signed a few seasons ago. Not only do few teams have that kind of cap room, but ultimately no one was interested in that kind of financial obligation for a 31-year-old backcourt player. Most guards decline precipitously after hitting the big three oh, and Iverson has taken so many hits in his stellar career that his decline might be steeper than most.

According the salary tracker at www.basketball-reference.com, Iverson has made almost $100 million playing basketball already. He’d probably be happy to trade some of the $60 million that’s due to him for a chance to play for a title (something that’s unlikely in Philadelphia, a team whose cap hell is surpassed only by the Knicks), but it won’t happen, a contract is binding. Instead, A.I.’s best chance at returning to the Finals will come if he stays healthy and signs on for the minimum with a contender in 2009–10. By that time, his game will almost certainly be a shadow of its present level. If he’s lucky he will be like Gary Payton this year, and it’s worth remembering that it took the Glove three years of wandering the league to luck into the right situation.

Shorter contracts give both team executives and players more flexibility, and they would bring some sanity to the free agent market. This summer was an opportunity to move in that direction, but the chance is gone.

mjohnson@nysun.com